Onderzoek naar de ammoniak- en geuremissie van stallen LI : beddenstal voor gespeende biggen = Adapted house for weaned piglets

Ammonia emission from animal husbandry has to be reduced in the Netherlands by 70% in the year 2005, compared with the emission level in 1980. Moreover, recently adapted odour legislation requires measurements of the odour emissions of the main conventional and new housing systems. Research was carried out into the emission of ammonia and odour from a house for weaned piglets with boxes. The research was carried out during a spring and summer period

Forecasting the Varibility of Stock Index Returns with Stochastic Volatility Models and Implied Volatility

In this paper we compare the predictive abilility of Stochastic Volatility (SV) models to that of volatility forecasts implied by option prices. We develop an SV model with implied volatility as an exogeneous variable in the variance equation which facilitates the use of statistical tests for nested models# we refer to this model as the SVX model. The SVX model is then extended to a volatility model with persistence adjustment term and this we call the SVX+ model. This class of SV models can be estimated by quasi maximum likelihood methods but the main emphasis will be on methods for exact maximum likelihood using Monte Carlo importance sampling methods. The performance of the models is evaluated, both within sample and out-of-sample, for daily returns on the Standard & Poor's 100 index. Similar studies have been undertaken with GARCH models where findings were initially mixed but recent research has indicated that implied volatility provides superior forecasts. We find that implied volati..

Modafinil reduces patient-reported tiredness after sedation/analgesia but does not improve patient psychomotor skills

Background: Early recovery of patients following sedation/analgesia and anesthesia is important in ambulatory practice. The aim of this study was to assess whether modafinil, used for the treatment of narcolepsy, improves recovery following sedation/analgesia. Methods: Patients scheduled for extracorporeal shock wave lithotripsy were randomly assigned to one of four groups. Two groups received a combination of fentanyl/midazolam with either modafinil or placebo. The remaining groups received remifentanil/propofol with either modafinil or placebo. Modafinil 200 mg was administered to the treatment group patients 1 h before sedation/analgesia. Groups were compared using the digital symbol substitution test (DSST), trail making test (TMT), observer scale of sedation and analgesia (OAA/S) and Aldrete score. Verbal rating scale (VRS) scores for secondary outcome variables e.g. energy, tiredness and dizziness were also recorded before and after treatment. Results: Sixty-seven patients successfully completed the study. Groups received similar doses of sedation and analgesic drugs. No statistically significant difference was found for DSST between groups. No significant adverse effects occurred in relation to modafinil. No statistically significant difference between groups was identified for TMT, OAA/S and Aldrete scores. The mean VRS score for tiredness was lesser in the modafinil/fentanyl/midazolam group [1.3 (2.0)] compared with the placebo group [3.8 (2.5)], P=0.02. Such a difference was not found between the remifentanil/propofol groups [placebo 2.6 (2.2) vs. modafinil 3.1(2.7)], p&gt;0.05. Dizziness was greater in the modafinil/remifentanil/propofol group 1.7 (2.0) vs. placebo 0.0 (0.5), p&lt;0.05. Conclusion: Modafinil reduces patient-reported tiredness after sedation/analgesia but does not improve recovery in terms of objective measures of patient psychomotor skills.</p

Fijnstofemissie uit stallen: vleesvarkens = Dust emission from animal houses: growing and finishing pigs

In this study emissions of fine dust (PM10 and PM2.5) from houses for growing-finishing pigs were determined. In addition, emissions of ammonia, greenhouse gases and odour were determined

Modafinil reduces patient-reported tiredness after sedation/analgesia but does not improve patient psychomotor skills

Background: Early recovery of patients following sedation/analgesia and anesthesia is important in ambulatory practice. The aim of this study was to assess whether modafinil, used for the treatment of narcolepsy, improves recovery following sedation/analgesia. Methods: Patients scheduled for extracorporeal shock wave lithotripsy were randomly assigned to one of four groups. Two groups received a combination of fentanyl/midazolam with either modafinil or placebo. The remaining groups received remifentanil/propofol with either modafinil or placebo. Modafinil 200 mg was administered to the treatment group patients 1 h before sedation/analgesia. Groups were compared using the digital symbol substitution test (DSST), trail making test (TMT), observer scale of sedation and analgesia (OAA/S) and Aldrete score. Verbal rating scale (VRS) scores for secondary outcome variables e.g. energy, tiredness and dizziness were also recorded before and after treatment. Results: Sixty-seven patients successfully completed the study. Groups received similar doses of sedation and analgesic drugs. No statistically significant difference was found for DSST between groups. No significant adverse effects occurred in relation to modafinil. No statistically significant difference between groups was identified for TMT, OAA/S and Aldrete scores. The mean VRS score for tiredness was lesser in the modafinil/fentanyl/midazolam group [1.3 (2.0)] compared with the placebo group [3.8 (2.5)], P=0.02. Such a difference was not found between the remifentanil/propofol groups [placebo 2.6 (2.2) vs. modafinil 3.1(2.7)], p&gt;0.05. Dizziness was greater in the modafinil/remifentanil/propofol group 1.7 (2.0) vs. placebo 0.0 (0.5), p&lt;0.05. Conclusion: Modafinil reduces patient-reported tiredness after sedation/analgesia but does not improve recovery in terms of objective measures of patient psychomotor skills.</p

U-drawing of Fortiform 1050 third generation steels. Numerical and experimental results

Elasto–plastic behavior of the third generation Fortiform 1050 steel has been analysed using cyclic tension–compression tests. At the same time, the pseudo elastic modulus evolution with plastic strain was analysed using cyclic loading and unloading tests. From the experiments, it was found that the cyclic behavior of the steel is strongly kinematic and elastic modulus decrease with plastic strain is relevant for numerical modelling. In order to numerically analyse a U-Drawing process, strip drawing tests have been carried out at different contact pressures and Filzek model has been used to fit the experimental data and implement a pressure dependent friction law in Autoform software. Finally, numerical predictions of springback have been compared with the experimentally ones obtained using a sensorized UDrawing tooling. Different material and contact models have been examined and most influencing parameters have been identified to model the forming of these new steels

Identification of regeneration-associated genes after central and peripheral nerve injury in the adult rat

Background: It is well known that neurons of the peripheral nervous system have the capacity to regenerate a severed axon leading to functional recovery, whereas neurons of the central nervous system do not regenerate successfully after injury. The underlying molecular programs initiated by axotomized peripheral and central nervous system neurons are not yet fully understood.Results: To gain insight into the molecular mechanisms underlying the process of regeneration in the nervous system, differential display polymerase chain reaction has been used to identify differentially expressed genes following axotomy of peripheral and central nerve fibers. For this purpose, axotomy induced changes of regenerating facial nucleus neurons, and non-regenerating red nucleus and Clarke's nucleus neurons have been analyzed in an intra-animal side-to-side comparison. One hundred and thirty five gene fragments have been isolated, of which 69 correspond to known genes encoding for a number of different functional classes of proteins such as transcription factors, signaling molecules, homeobox-genes, receptors and proteins involved in metabolism. Sixty gene fragments correspond to genomic mouse sequences without known function. In situ-hybridization has been used to confirm differential expression and to analyze the cellular localization of these gene fragments. Twenty one genes (similar to 15%) have been demonstrated to be differentially expressed.Conclusions: The detailed analysis of differentially expressed genes in different lesion paradigms provides new insights into the molecular mechanisms underlying the process of regeneration and may lead to the identification of genes which play key roles in functional repair of central nervous tissues